Development of somaclones and their genetic diversity analysis through RAPD in Finger millet (Eleusine coracana L. Gaertn.)

Abstract

While developing a protocol for induction of variability in vitro in finger millet, significant differences for callus induction among genotypes, explant types, culture medium and their interactions were observed. The genotypes, IVT 10 (52.25%), IPGSM 10 (27.90%) and IVT 4 (23.60%) showed significantly higher frequencies of callus induction as compared to other genotypes. All the genotypes and explants showed highest callus induction in MS + 2 mgl-1 2,4-D. MS medium induced early callus than B5 media. Nine out of 12 genotypes showed somatic embryogenesis and morphogenesis. However, genotypes IPGSM 18, GOA 8/1 and AVT 11 failed to regenerate. Among explants, mature embryo axes showed highest (25.68%) regeneration response in nine genotypes. Half strength MS medium supplemented with 0.2 mgl-1 IBA + 0.1 mgl-1 BAP and 2 per cent sucrose showed significantly higher number of roots (10.25) in 6.55 days. The rooted plants planted in pots containing soil, sand and vermiculite in equal proportion showed 60% survivability in six genotypes. A total of 10 primers were used for amplification of genomic DNA of the 6 parents and their 45 variants for RAPD analysis. Out of 1374 amplified fragments 1268 (92.59 %) DNA fragments were monomorphic while the remaining 106 (7.41%) were polymorphic. The RAPD based dendrogram indicated subgrouping of IVT 10 variants and data showed genetic distance between the variants.